gprofng: fix build problems on linux-musl

gprofng: fix build problems on linux-musl

ino64_t, off64_t, fpos64_t, stat64, __u64 are not defined on linux-musl.
Fixed by declaring these types for linux-musl.

2023-12-21  Vladimir Mezentsev  <vladimir.mezentsev@oracle.com>

	PR gprofng/30779
	PR gprofng/29593
	* common/gp-defs.h: Define ino64_t, off64_t, fpos64_t for linux-musl.
	* libcollector/unwind.c: Define __u64 for linux-musl.
	* src/util.h: Define dbe_stat_t.
	* src/ClassFile.cc: Use dbe_stat_t instead of "struct stat64".
	* src/Dbe.cc: Likewise.
	* src/DbeFile.cc: Likewise.
	* src/DbeFile.h: Likewise.
	* src/DbeSession.cc: Likewise.
	* src/Experiment.cc: Likewise.
	* src/checks.cc: Likewise.
	* src/util.cc: Likewise.